In the field of tufting carpets, it has been known to tuft carpets having spaced rows of loop pile and cut pile tufts, including the formation of loop pile and cut pile tufts in the same longitudinal tuft rows of the carpet. For example, U.S. Pat. No. 3,919,953 discloses an apparatus and method for tufting spaced rows of loop pile tufts and cut pile tufts in a backing material using a multi-needle tufting machine having spaced transverse rows of needles that cooperate with a series of loop pile loopers or cut pile hooks mounted on the upstream and down stream sides, respectively, of the tufting machine.
Additionally, patents such as U.S. Pat. Nos. 6,155,187 and 7,007,617 disclose level cut loop hook or looper assemblies for tufting machines for selectively forming cut pile and loop pile tufts in a backing material. Such level cut loop hook assemblies generally include a cut pile hook and a slideable clip that can be moved into a position in engagement with the hooked front end of the level cut loop hook so as to block or otherwise prevent loops of yarns from being retained on the level cut loop hook and thereafter cut by an associated reciprocating cutting blade. Alternatively, other designs have been proposed in which a clip slides along or bears against the sides of a loop pile looper to facilitate capturing of the loops of yarn on the looper for cutting by the associated cutting blade.
A problem that exists with many conventional level cut looper/hook assemblies is, however, that the loops of yarn being formed about the clips and hooks when the clips are in their extended position often are not uniformly formed, especially in comparison with the cut pile tufts, which can result in a pile height differential between the cut and loop pile tufts. In addition, when the clips are in their fully extended positions, the loops of yarn carried by the needles being engaged by the hooks and clips sometimes are not picked cleanly and can be backrobbed by the return stroke of the needles. Consequently, it often is necessary to run the needles at a deeper stroke or depth so as to ensure that the needles will penetrate the backing material to a depth sufficient to be engaged and their yarns picked substantially cleanly therefrom during a tufting operation. As a result, the level cut loop tufting machines generally must be run at slower operating speeds to accommodate such greater penetration depths and to minimize other problems such as backrobbing of the yarns.
According, it can be seen that a need exists for a level cut loop hook/looper and clip assembly that addresses the foregoing and other related and unrelated problems in the art.